V3: Async operations helper

[kobajagi]

Helper that waits on async operation to complete.

Example usage:

    op, err := client.Wait(
        context.Background(),
        func(ctx context.Context) (*oapi.Operation, error) {
            return client.Compute().LoadBalancers().Create(ctx, body)
        },
    )
    if err != nil {
        panic(err)
    }
    fmt.Println(*op.State, *op.Reference.Id)

[shortcut-integration[bot]]

This pull request has been linked to Shortcut Story #71885: Async operations helper.